Process for separation of ingredients of mixed solid materials.



F. S. MAGGREGOR- I PROCESS FOR SEPARATION OF INGREDIENTS OE MIXED SOLID MATERIALS.

- APPLIOATION'FILED FEB. 27, 1909.

' Patented Oct. 11,1910.

&

of Lynn, Massachusetts.

nnresnn snares. PATENT anion FRANK SANDERSON MAGGREGOR, 0F HYDE PARK, MASSACHUSETTS, ASSIGNOR TO HUFF ELECTROSTATIC SEPARATOR COMPANY, OF

.TION OF MAINE.

BOSTON, MASSACHUSETTS, A CORPORA- PROGESS FOR SEPARATION OF INGREDIENTS OF MIXED SOLID MATERIALS.

Specification of Letters Patent.

' Application filed February 27, 1909. Serial No. 480,400;

To all whom it may concern:

Be it known that I, FRANK SANDnRsoN MACGREGOR, a citizen of the United States, and resident of Hyde Park, in the county of Norfolk and State of Massachusetts, have invented new and useful Improvements in Processes for Separation of Ingredients of Mixed Solid Materials, of which the followin is a specification.

y invention relates to the separation or concentration of the ingredients of mixtures of comminuted solid materials, such as the miscellaneous components of rock or earth in which valuable ores are found, and consists in an improved method by which different ingredients of such mixtures may be classified or concentrated in groups of particles, each group composed of particles which possess some common characteristic.

My improved process takes for its starting point of development a method of separation invented by Henry Azor Wentworth Said process of separation invented by Mr. Wentworth, briefly described, consists in placing a mixture of miscellaneous comminuted particles upon a liquid, under the influence of chemical treatment which so differentially m'odifiesthesuperficial character of the several particles, that their respective and relative avidities for the liquid are changed; some may, under this treatment, assume an abnormal aversion for the liquid while others assume an abnormal avidity for it. Whether one or both of these phenomena be present,

the result is an enhanced contrast of the several ingredients of the mixture in respect to the readiness with which their surfaces become moistened with thedliqui'd on which the materials are placed; in one of its aspects Mr. Wentworths process is that of enforced and positive wetting and consequent engulfment of a portion of the mass under treatment, which, under normal conditions, would be sustained in whole or in part by the surface tension, of the liquid on which the particles are placed. More specifically considered, Mr. WVentworths invention consists inthe treatment of ores containing metallic sulfids notably zinc sulfid, by contact with a halogen and the deposition of the comminuted materials upon the surface of a body of water; the halogen, such as chlorin, in some cases increases the aversion for water of one of the sulfids, apparently leaving the other ingredients in their normal condition in respect to the readiness with which they become wetted in other cases none of the ingredients of the mixture is rendered abnormally resistant to wetting, but some are made abnormally susceptible thereto; intboth cases, the result is a separation of those particles which are wetted and engulfed from those which remain sustained by surface tension and are floated to any desired place of deposit.

While my invention, which is the subject of the following specification, may be in practice characterized by both the above described phenomena; as an improved method,

it depends more upon the artificial imposition of an abnormal avidity for a liquid, upon particles placed in contact with the liquid, and may be characterized further by a progressive action by which particles may be classified according to the length of time required, under the conditions imposed, for each group or set-of particles to become wetted and engulfed by the liquid on which the mass as a whole is initially deposited. Moreover, this progressive differentiation of particles, according to the various times required for them to become wetted by a liquid, may be taken advantage of without any artificial treatment when the normal conditions presented by the material are favorable, but as a rule I believe that it will be found advantageous to affect the particles differentially by chemical treatment so as to produce or enhance dilferences in the sus- Patented Get. 11, ioio.

cepti-bility of the various particles to superficial Wetting by the liquid.

In the drawings hereto annexed there is illustrated an apparatus by which my process in its several aspects may be advantageously carried on.

Figure 1 is a vertical longitudinal section of a separator; and Fig. 2 is a View in perspective of one of the agitatorswhich form part of the structure shown in Fig. 1.

The apparatus illustrated consists of a preferably closed tank A, whereof a cover portion B may be made of glass in order to afford a view of the interior. The separator tank A is divided into compartments by vertical partitions D, D, D D D and each of these compartments terminates in a recogtacle, the latter being shown atG, C,

C C C and at the lower ends of these compartments are provided means for drawing off their contents such as cocks E, E, E E E E For purposes of inspection glass covered peep holes ma be provlded at U, U, U U U U In t e firstor upper of the divisions of the separator tank A there is transversely mounted a roller I which may advantageously be covered with. 1 cloth so as to present a suitable surface for the reception of the comminuted material which is fed from a hopper K over a small roller L, the feed being regulated by a shutter M. This feed may be inspected through the glass plate N which forms a portion of one side of the hopper K. The rollers I and L may be rotatedysimultaneous'ly by means of a belt shown in dottedlines at C; the driving power may be supplied from any suitable source. Across the top of each of the partitions D, D, D D D there extend strips T, T, T T T, which are hinged by means of a watertight flexible joint. These hinge-strips are secured to and carry the agitator plates oraprons P, P, P P P and on the upper surface of several of these aprons there are fixed a suitable number of obstructions shown in the drawings as pins 7). The lower ends of the aprons P, P, P P, P, are suspended by cords R which are wound upon Windlass pins S so that by turning the latter, the inclination of the aprons P, P, P P P P may be altered. The upper edges of these aprons, together with the hinge-strips T, T, T T T constitute weirs, and the force with which liquid descending over the aprons impinges against the upper surface of the next adjacent weir, depends upon the adjustment of the apron by means of the cord R. The lowermost apron, P, is preferably smooth, or in other words, not provided with any obstructions to the passage of liquid, and its inclination is also preferably adjusted at a more abrupt angle than that of the aprons above it in the series, so that material, both a solid and liquid, sliding down the apron P will be discharged against the end Wall D violently as contrasted with movements of similar material over the upper aprons in the series. The separator tank is filled to the desired extent with liquid from the pi e F and whena desired quantity of liquid has been supplied and the flow through pipe F is stopped, its circulation is controlled and kept up by means of the pump G which draws the liquid from the lowest compart= ment of the series through pipe F and delivers it to the head of the separator tank through pipe F.

An operation of the above described apparatus is as follows: Liquid is run into the separator tank filling the compartments in succession until the level in the lowermost 65 compartment stands at a desired height, say

vala 'd that represented'by the dotted 11116 2. The

level in the uppermost compartment will be at the dotted line 1, as high as that of the first weir formed by the upper edge of the apron P. The supply of liquid then being shut olf, operation of the pump G causes the liquid to circulate in rotation, maintaining the levels in the uppermost and lowermost compartments substantially constant. Comminuted solid material is now introduced into the hopper K and is fed over the roller L from which it falls onto the roller 0. The rate'of rotation of the roller 0 should be gentle and I prefer to adjust it so that the rate of movement'of the material deposited upon this roller shall be approximately equal to the rate of flow of theliquid toward the apron P. Capillary attraction causes the liquid to creep up on the roller 0' to a slight extent and when the material in the movement of the roller 0 comes in contact'with this liquid, it is slid onto the surface of the liquid gently and with as little agitation as is practicable so that the surface tension of the liquid may operate to its full capacity to sustain the particles. Let us suppose that there are in the mixture of solids six classes of ingredients, of which the first is composed 0f particles which are, for one reason or another, incapable of being sustained by the surface tension of the liquid in the separator, and that the five other mgredients are com posed of particles which will, under the conditions of gentle deposition from the roller 0, be sustained by the-surface tension of the liquid, but that class 2 is of such a character that its particles will not endure any agitation of-the liquid without becoming thoroughly wetted and engulfed, and that class 3 will endure the agitation better than class 2 or for a longer time, and that classes 4, 5 and 6 are similarly graded in series in respect to the persistence with which they resist Wetting by the liquid on which they are placed. Under these supposed conditions particles belonging to class 1 will thereupon on their first contact with the liquid, or very shortly after, become wetted thereby and sink into the first receptacle C. As the liquid carrying the other particles on its sur-' face travels over the apron P, the gentle agitationcaused by the pins p, stirs up the solid particles to an extent sufficient to cause class No. 2 thereof to be wetted and these are arrested at the weir formed by the hinge-strip T and the upper edge of the apron P and fall into the com artment C. sive series-of agitations continues until the The progrespersistently floating particles which form the in the lowermost compartment. The agita-,

'tion caused by this movement is sufficient to cause the wetting and engulfment of the last group of particles in the series.

It will be understood that the classifica tion or differentiation of the deposited contents in the several compartments is one which relates primarily to differences in .behavior toward the liquid, and may or may not involve a classification of different sub stances. The substance of all the deposits, say, save the lastone may be the same, as in the instance presently to be described. Take for example an ore mixture in which zinc sulfid and iron sulfid are the chief ingredients to be separated, where the gangue either may be a harmless accompaniment of zinc or iron sulfid, or may be readily separated from either by a preliminary or subsequent process. With such a sulfid mixture, the treatment contrived by Mr. VVentworth may advantageously be employed; this involves exposing the ore mixture, when wet, to the action of a halogen, such as chlorin. For this purpose I provide a pipe H which extends across the separator tank near the roller 0 and is perforated, and through the pipe and its perforations I introduce chlorin gas which presently forms a chlorin atmosphere in the upper portion of the separator tank and gradually goes into solution in the liquid, water, with which the tank is supplied. The effect of the chlorin atmosphere and chlorinated liquid is to increase the aversion for water, naturally possessed to some degree by Zinc sulfid, whereas in the case of an iron sulfid, such normal avidity as this material has for water is greatly increased and the same is true to some degree, of the other ingredients of the mixture. Though all'of the comminuted ingredients may be reduced to such small dimensions that, in spite of their great specific gravity, they will be normally sustained by the surface tension of water, no sooner has the mass of particles proceeded a short distance from the point where the roller 0 delivers them to the surface of the water, than the ma jority of iron sulfid particles, under the chlorin treatment, acquire such an avidity for water that they become wetted and sink, a phenomenon which maybe observed by looking through the peep-hole at U. A large proportion of the iron sulfid behaves in this manner in the upper compartment, usually leaving however, such a quantity of iron sulfid still floating with the zinc sulfid as would, if allowed to remain in the same classification as the zinc, seriouslyra'lfect the smelter value of the zinc product, but as soon as the effect of the agitators, such as apron P, is brought to bear, those particles of iron sulfid which remain on the surface of the water are in their turn wetted and sink in a lower compartment; the agitation -of-- the liquid surface which is carrying the iron sulfid particles assists in bringing about on such particles the chemical reaction with the chlorin which is relied on to increase the superficial avidity of these particles for water. Iron sulfid particles which for any reason have escaped the reaction, or require a longer exposure to the reagent in order to undergo the superficial change, are given a protracted opportunity for association with the chemical reagent; so in series the differentiation and group deposit of the particles continues until the class of zinc sulfid alone is delivered to the apron P, where, by the reason of the abruptness of the descent of the liquid and solids together over the apron, the zinc sulfid is finally wetted, immersed and sinks to the bottom of the compartment C". ents may then be drawn off from the several compartments through the cocks provided for the purpose in the form of pulp or mud which may be thereafter treated as' desired.

The segregated and classified ingrediof the particles constituting two or more ingredients, thereafter subjecting the material to chemical treatment while on the liquid, to alter the superficial condition of some one or more of said ingredients and thereby rendering the particles thereof abnormally susceptible to wetting by the said liquid, in contrast to the persistent condition of other ingredient particles, engulfing said wetted ingredients in the liquid and separately collecting the immersed and floated ingredients.

2. The process of separating ingredients of comminuted solid material, which consists in depositing the material gently upon the surface of a liquid, under conditions, as

to comminution of the material, favorable to the flotation by surface-tension of the particles constituting two or more ingredients, thereafter subjecting the floated materials to chemical treatment while on the liquid, to alter the superficial condition of some one or more of said ingredients and render the particles thereof abnormally susceptible to wetting by the said liquid, in contrast to the persistent condition of other ingredient particles, subjecting the materials and the liquid to gentle agitation, accompanied by flow in one direction, engulfing the wetted particles in the liquid, and separately collecting the immersed and floated ingredients.

3. The process of separating ingredients of comminuted material containing metallic sulfid, which consists in depositing the materials gently upon the surface of a body of water, under conditions, as to comminution of the material, favorable to flotation by surface tension of the particles constituting two or more ingredients, subjecting the materials to contact with a halogen while on the water, to increase the superficial avidity for water of some one or more of said ingredients, in contrast to the persistent condition of other ingredient particles, etting and engulfing the particles affected as aforesaid by the halogen, and separately collecting the immersed and floated ingredients.

4. The process of separating ingredients of comminuted material containing metallic sulfid, which consists in depositing the materials gently upon the surface of a body of Water, under conditions as to comminution of the material, favorable to flotation by surface tension of the particles constituting two or more ingredients, subjecting the materials to contact with a halogen while on the water, to increase the superficial avidity for Water of some one or more of said inedients, in contrast to the persistent conition of other ingredient articles, subjecting the materials and the liquid to gentle agitation accompanied by flow in one direction, engulfing the wetted particles and separately collecting the immersed and floated ingredients.

. 5. The process of separating ingredients of comminuted solid material, which consists in depositing the material gently upon the Surface of a liquid, under conditions as to comminution 0f the material favorable to the flotation by surface nsion of the particles constituting the several ingredients, thereafter subjecting the floated materials to chemical treatment while on the liquid, to

alter the superficial condition of one or more of the said ingredients and render the particles thereof abnormally susceptible to wetting by the said liquid, subjecting the liquid and the particles of solid material to a series of consecutive agitations, accomp flow in one direction, and successively wetting and engulfing the particles aflected, in the order of their susceptibility to the liquid, and separately collecting the ingredients thus separated.

6. The process of separating ingredients of. comminuted material containing metallic sulfids, which consists in depositing the materials gently upon the surface of a body ofwater, under conditions, as to comminution of the material, favorable to the flotation by surface tension of the particlesconstituting anied by engulfing the particles affected, in the order, of their susceptibility to the water and sepa"- rately collecting the ingredients thus separated.

7. The process of separating ingredients of comminuted solid material, which consists in depositing the material gently upon the surface of a liquid under conditions,as

' to comminution of the material, favorable to the flotation by surface tension of the particles constituting the several ingredients, thereafter subjecting the floated mat arials to chemical treatment while on the liquid, to alter the superficial condition of one or more of the said ingredients and render the particles thereof abnormally susceptible to wet,- ting by the said liquid, subjecting the liquid and the particles of solid material to a series of consecutive agitations whereof the last is violent as compared with preceding agitations, successively Wetting and engulfing the particles affected, in the order of their sus-' ceptibility to the liquid, and separately collecting the ingredients thus separated.

8. The process of separating ingredients of comminuted solid material containing me.-. tallic sulfids, which consists in depositing the materials gently upon the surface of a body of water under conditions, as to comminution of the material, favorable to the flotation by surface tension of the particlesconstitutin'g the several ingredients, thereafter subjecting the materials to contact with a halogen while on the water, to increase the superficial avidity for water of one or more of said ingredients, subjecting the water and the particles of solid material to a series of successive agitations whereof the last is violent as compared with preceding agitations, successively wetting an engulfing the particles affected, in the order of their susceptibility to Water, and separately collecting the ingredients thus separated.

Signed by me at Boston, Massachusetts, this twenty-fifth day of F ebruai'y,-1909.

FRANK SANDERSON MA GGREGOR- Witnesses ODIN ROBERTS, r ROBERT CUsHMAN. 

